old visa open

[gimazz]

Hi All,

I've a problem connecting an HP Agilent 6033A, running the "HP6xxxA initialize.vi" it tells me: error out: code:-1073807194 source: "Old VISA Open in HP6xxxA Initialize.vi". What kind of error it is?

I have "instrument descriptor: GPIB::5"  (default)     "VISA session (for class): (3 choices) COM1 , GPIB0::0::INSTR , LPT1"      

I tried to change them and run again but it seems doesn't work

The HP power supply is connected via GPIB-USB-B to the PC and gives power to a flexible heater;

Waiting a prompt reply

thank you very much

[Dennis_Knutson]

You should replace the Old VISA Open with the VISA Open that is on the VISA>VVISA Advanced palette. Delete the instrument descriptor string control. Then you can click on the VISA Session control to select the actual VISA resource from the pull down menu.

The other option is to install the current driver which is a project style driver. This does not use the old VISA Open. A project style driver can be used with any version of LabVIEW from 8.0 or higher. If you had used the Help>Find Instrument Drivers, this is the driver that would have been installed.

[gimazz]

OK now the HP6033A talks with the PC, (RMT led is on, and LST, TLK leds are flashing), but every some secs it has a loss of voltage, and the signal falls down to rise up instantly, could be caused by this change of communication?

Thank you Dennis!

[Dennis_Knutson]

I don't quite understand. The output changes after you have programmed it? Other than the initialize function, what else did you change? Is the VI stopped when you see the output change?

[gimazz]

I've used your first solution, so replaced "old visa open" with "visa open" in the HP6xxxA initialize deleted the instrument descriptor and used the GPIB--INSTR choice in the visa session menu; I changed nothing apart GPIB initialize; the VI doesn't stop, it continues but the HP6033A has voltage falling to zero and raise to the correct one every about 3s; thanks for your patience

[gimazz]

sorry I mean "HP6xxxA initialize" 🙂

[Dennis_Knutson]

You are going to have to post your VI or at least attach an image of what you have in your while loop.

[gimazz]

ok, here it is;

[Dennis_Knutson]

I don't have the obsolete driver installed - just the project style driver so I don't know what some of the subVIs are doing. Step through it and see where the output voltage is dropping.

[gimazz]

Ok, I think I've found when I've the voltage drop: In my VI I have 2 thermocouples working on the same device, a NI 4351PCI. I've seen that at the same time of the voltage drop, the 2nd thermocouple stops to acquire. If I use only one of them ( sacrifying one channel) the drop doesn't appear; how I can work with two thermocouples without having a stop of the acquisition? Maybe changing some NI4351 parameter? Ty